James tripp



(No Model.)

J TRIPP.

I TAKE-UP MECHANISM FOR SEWING MACHINES.

Patented Mar. 19, 1889.

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JAMES TRIPP, O F NEWV'YORK, N. Y.

TAKE-UP MECHANISM FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 399,949, dated March 19, 1889.

Application filed December 4, 1888- Serial No. 292,616. (No model.)

To aZZ whom it may concern:

Be it known that I, JAMES TRIPP, a citizen of the United states, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Take-Up Mechanism for Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawin s.

The object of my invention is to provide a simple and effective take-up mechanism for sewing-machines which will have all of the advantages as to timing and positive and reliable action of the cam-operated take-ups now largely in use, while it avoids the objections incidental to the use of a grooved cam at the forward. end of the needle-bar-operating shaft. Owing to the position of the camcylinder near the forward end of the upper shaft, an unsightly swell or bulge must necessarily be given to the forward end of the overhanging bracket-arm in machines employing take-ups operated from grooved cams formed in the peripheries of cam-cylinders thus located, and while such swell or bulge is objectionable in appearance, the reliability of action and perfect timing afforded by the grooved cams has rendered their use desirable notwithstanding the above-noted objection and the more serious one of friction and wear incidental to the use of such cams.

In my improved take-np mechanism the main take-up is a swinging arm arranged in front of the face-plate of the machine and carried by a small rook-shaft journaled above the main or needle-bar-operating shaft, and provided within the head with an arm having a cam-slot, into which the crank-pin of the needle-bar pitman (or an independent pin on said pitman) extends to vibrate said rockshaft and the take-up arm as the needle-bar is operated. An auxiliary take-up, which is attached to the needle-bar, engages the thread between the tension device and the eye of the main take-up, and serves to hold the thread taut while the needle-bar is descending and until it reaches the limit of its downward movement, so that there will be no objectionable slack thread hanging loose at any time.

I11 the accompanying drawings, Figure l is a sectional, side view of the head of a sewingmachine with my improvement applied thereto. Figs. 2, 3, and 4 are front views of the same with the parts in difierent positions. Figs. 5 and 6 are detail views, to be referred to.

A denotes the head at the forward end of the sewing-machine bracket-arm, and B the main or needle-bar-operating shaft, carrying the usual crank-disk, Z), provided with the crank-pin I).

O is the needle-bar operatively connected with the crank-pin b by the pitman c, the cross-bar c at the lower end of which is preferably extended into a groove, a, in the head A, and provided with an anti-friction roller, 0 to give steadiness of movement to the needle-bar and to the take-up mechanism. The main take-up is a depending swinging arm, D, arranged in front of the faceplate o, and rigidly attached to a small rockshaft, (Z, journaled in the upper part of the head, and provided within the latter with an arm, (1, having a cam-slot, (1 into which the crank-pin Z) extends, said slot being of such curvature as to operate the rock-shaft d to effect the entire take-up movement during somewhat less than a quarter-revolution of the main shaft 13.

Connected with the needle-bar is the auxiliary take-up aeXtending outward through a slot in the face-plate, and consisting, preferably, of a wire or other spring device adapted to engage the thread running from the tension-disks f through the thread-guide g to the eye (Z at the lower end of the takeup arm D. This auxiliary take-up is preferably attached to a plate, 6, which is adjustably secured to the needle-bar by a screw or screws passing through a slot or slots in the said plate, so that the position of the auxiliary take-up maybe varied as may be desired, to get the exact timing necessary. Thethreadguide g is also preferably made adjustable vertically by being carried by an adjustable plate, 9, attached to the faceplate a by a screw, 1 passing through a slot, 9 in said plate g. The thread runs from the eye d of the main take-up through one or more threadguides, h, on the face-plate downward to the needle.

The operation of my improved take-up mechanism is as follows: When the needlebar is at the upward limit of its movement, the main take-up arm hangs vertically, as

shown in Fig. 2, so as to entirely slacken the thread to afford the full size to the loop through which the shuttle has at this movement just passed; but during the time that the shaftB is next performing less than a quarter-revolution the crank-pin b, traveling in the camslot of the arm d, will cause the take-up to move quickly from the position shown in Fig. 2 to the fully outward position shown in Fig. 3, thereby taking up the entire slack of the loop through which the shuttle has passed and tightening the stitch. During the time that the main take-up was operating to tighten the stitch the auxiliary take-up e (owing to the elevated position of the needle-bar by which it is carried) was above the thread running from the tension device through the thread-guideg to the eye of the main take-up D, so as to leave the thread entirely free while the stitch was being tightened but as the take-up D swings inward and slackens the thread the said auxiliary take-up moves downward with the descending needle-bar and holds the thread taut until the needle cl by the crank-pin b, which actuates the neebar has reached the limit of its downstroke, as in Fig. 4, so that there will be no slack to get in the way of the needle or to be entangled and thus cause liability of breaking the thread. As the needle-bar rises, the needleloop is thrown out in the usual manner, and is seizedby the shuttle, which expands and passes into it, and thus the needle-thread is held taut by the shuttle until the latter has passed through the loop, when the main takeup quickly operates as before to tighten the stitch. Thus the operations continue, the needle-thread being at all times controlled with the greatest nicety by the take-up or thread-controlling mechanism, so as to be held taut when desired, and still be yielded up to the shuttle when the latter is to pass through the loops of needle-thread.

Instead of operating the take-up rock-shaft dle-bar, said shaft may be operated by an independent crank-pin, b carried at the upper end of the pitman o, as shown in the detail views, Figs. 5 and 6. By thus operating said rock-shaft a greater throw (with the same curvature of the cam-slot d of the arm (1) can be given to the take up arm, and this construction may therefore be preferable for some machines employing large shuttles requiring large loops of needle-thread.

It will be obvious that by the adjustability of the positions of the auxiliary take-up and of the co-operating thread-guide {1 great exactness in the timing of the parts may be secured, and great nicety in the operation of the thread-controlling mechanism can thus be effected.

My improved take-up mechanism herein shown and described is especially adapted for machines having oscillating or rotating shuttles or rotary hooks, but with slight modifications might be adapted for other machines.

Having thus described my invention, I claim and desire to secure by Letters Patent 1. In a sewing-machine, the combination, with the head, the needle-bar, and actuating mechanism for the latter, of a take-up rock-- shaft having take-up and cam-slotted arms, an auxiliary take-up carried by said needlebar, and a co-operating thread-guide adj ustably secured to the face-plate adjacent to said auxiliary take-up.

2. In a sewing-machine, the combination, with the head, the needle-bar, and actuating mechanism for the latter, of a take-up rockshaft within said head, and having take-up and cam-slotted arms, an auxiliary take-up or slack-controller carried by the said needlebar, and a co-operating thread-guide secured to the face-plate of the head adjacent to the path of the said auxiliary take-up or slackcontroller.

'3. In a sewing-machine, the combination, with the head thereof having a face-plate provided with a vertical slot, the needle-bar-actuating shaft, and the needle-bar operatively connected with the said shaft, of a rock-shaft having a swinging take-up arm outside of the said face-plate and a cam-slotted arm within said head, a crank pin engaging the slot of the lastrnamed arm, and an auxiliary take-up or slack-controller carried by the said needlebar and extending outward through the said vertical slot in the face-plate.

In testimony whereof I affix my signature in presence of two witnesses.

JAMES TRIPP. WVitnesses:

HENRY GALVER, RUTLEDGE WILsoN. 

